Sanitary napkins having side flaps are disclosed in the literature and are generally available in the marketplace. Generally, the flaps extend laterally from the side edges of a central absorbent structure and are intended to drape over the edges of the wearer's panties in the crotch region. Thus, the flaps are disposed between the edges of the wearer's panties in the crotch region and the wearer's thighs. Commonly, the flaps are provided with an attachment means for affixing the flaps to the underside of the wearer's panties.
The flaps serve at least two purposes. First, the flaps prevent exudates from soiling the edges of the wearer's panties and second, the flaps, when affixed to the underside of the panties, help stabilize the napkin in the undergarment and prevent it shifting out of place.
Sanitary napkins having flaps are disclosed in U.S. Pat. No. 4,687,478, entitled “Shaped Sanitary Napkin With Flaps”, to Van Tilburg on Aug. 18, 1987, U.S. Pat. No. 4,608,047, entitled “Sanitary Napkin Attachment Means”, to Mattingly on Aug. 26, 1986, U.S. Pat. No. 4,589,876, entitled “Sanitary Napkin”, to Van Tilburg on May 20, 1986, U.S. Pat. No. 4,285,343, entitled “Sanitary Napkin”, to McNair on Aug. 25, 1981, U.S. Pat. No. 3,397,697, entitled “Disposable Sanitary Shield For Undergarments”, to Rickard on Aug. 20, 1968, U.S. Pat. No. 2,787,271, entitled “Sanitary Napkin”, to Clark on Apr. 2, 1957 and U.S. Pat. No. 4,900,320, entitled “Sanitary Napkin With Undergarment Gathering Flaps, to McCoy on Feb. 13, 1990, all of which are incorporated herein by reference in their entirety.
While sanitary napkins having flaps are commonly viewed as providing better protection against soiling as compared to sanitary napkins without flaps, these napkins commonly experience a problem that keeps them from being optimally effective.